Immunochemical study of chromatin non-histone proteins. I. Production of antibodies against rat thymus and liver chromatin; analysis of tissue specificity and intranuclear distribution of immunogenic proteins.

Rabbit antibodies against rat thymus and liver chromatin are obtained. Antithymus IgG are found to interact only with homologous chromatin, while antiliver IgG interact with both liver and thymus chromatin. After preincubation of antiliver IgG with thymus chromatin the antibodies interact with homologous chromatin only. Thus chromatin of both organs contains tissue-specific proteins. Antiliver and antithymus IgG are used to investigate a distribution of tissue-specific and tissue-non-specific immunogenic proteins in thymocyte nuclei. It is shown that these proteins are practically lacking in nuclear membranes, matrix, nuclear sap, nucleous chromatin and do not participate in attaching DNA to the nuclear matrix.